BASF and the Swedish packaging manufacturer BillerudKorsnäs have cooperated to develop a unique home-compostable paper laminate for flexible packaging. The multi-layer film consists of three basic components: BillerudKorsnäs‘ paper ConFlex Silk, a sealing layer made of BASF’s certified home compostable and partly bio-based biopolymer ecovio and BASF’s water-based adhesive Epotal Eco 3675 X which joins the film to the paper. As all parts of the multi-layer laminate are food-contact approved, it can be used to produce wraps with individually adjusted barrier properties, e.g. for cookies, ice cream, cereal bars and dairy items as well as wrappers for fish, meat and cheese freshly sold in supermarkets. All components are certified home-compostable according to official European certification schemes for home-composting. The laminate contains a high share of renewables and extends the end-of-life options for multi-layer flexible packaging by being organically recyclable.
The new home-compostable solution has the same performance features as conventional multi-layer packaging: It is puncture resistant, shows a good printability, excellent heat-seal properties and can be processed on standard packaging machines. “We wanted to create a paper-based laminate with good heat-seal properties by using certified home-compostable components only”, says Amir Pourirani, head of global marketing Biopolymers at BASF. “There is a huge trend in society, in some countries driven by legislation, to move from plastic to paper-based packaging. Moreover, currently available multi-layer flexible films are difficult to recycle but the technical need is still present. In BillerudKorsnäs we found the ideal partner to develop a home-compostable solution based on paper with a broader end-of-life option for packaging while maintaining the technical performance of traditional laminates.“ According to the targets of the „European Strategy for Plastics in a Circular Economy“ all plastic packaging should be recyclable or reusable by 2030.
“With BASF’s certified home-compostable biopolymer and adhesive, we found the ideal components to take the next step towards another sustainable solution for flexible packaging in our portfolio”, says Markus Saari, business development manager at BillerudKorsnäs. “Our joint development represents a shift to paper-based and compostable material in order to replace traditional laminates for food packaging - meeting hygiene and barrier requirements, maintaining form and enabling many design possibilities just like conventional packaging but with the decisive added benefit that it is home-compostable.”
The sealable laminate is produced in a wet lamination process. The outer layer consists of BillerudKorsnäs’ home-compostable kraft paper ConFlex Silk, which is certified according to OK Compost Home by TÜV Austria. It shows good printability and high strength at a weight of 60 g/m². It is based on a mix of 100% primary fibers. The inner sealing layer of the flexible packaging is made of a blown film out of a particular ecovio grade by BASF, which also holds the “OK Compost Home” certification by TÜV Austria.
The film is suitable for mono and co-extrusion and easy to seal. The sealing is laminated to the paper layer with BASF’s water-based dispersion Epotal Eco 3675 X. This adhesive is certified by DIN Certco as home-compostable according to DIN EN 13432, testing basis NF T 51-800. It can be processed like other adhesives by use of standard lamination machines and shows an excellent performance on different biodegradable substrates.